Sheet material processing apparatus, press die, and die setting body

ABSTRACT

A sheet material processing apparatus has a pressurizing part of a sheet material and a supporting part of the pressurized sheet material. The apparatus includes an end face pressing upper press die that receives a pressurizing force, an end face pressing lower press die that is arranged on the supporting part and faces the end face pressing upper press die so that an end face of the sheet material is inserted between the end face pressing upper and lower press dies, an end face pressing part that, with the end face pressing upper press die being moved toward the end face pressing lower press die, presses the end face of the sheet material, and an end face pressing width adjusting part that sets a pressing width of the end face of the sheet material.

TECHNICAL FIELD

The present invention relates to a processing apparatus for processing ametallic sheet material, a press die, and a die setting body, andparticularly, to a sheet material processing apparatus having a functionof bending a sheet material and/or a function of pressing an end of thesheet material.

BACKGROUND ART

Laser-cutting or shearing a metallic sheet material, and thereafter,bending the sheet material frequently cause a warp S such as a boat warpon the sheet material W as illustrated in FIG. 12. It is known that thewarp S occurs when the sheet metal W to be bent has a relatively smallwidth and a relatively long ridge to be bent.

To suppress such a warp on a sheet material, the sheet material, whichhas been cut, is passed through a leveler and bent, or is first bent bypress machine, reversed, and pressed to correct a warp. Using a levelerhas a problem that a leveler capable of dealing with sheet materials ofvarious sizes must be prepared between a cutting process and a bendingprocess. Bending a sheet material by press machine and then correcting awarp have a problem that the warp correction is difficult.

Japanese Unexamined Patent Application Publication No. 2005-177790(Patent Literature 1), for example, provides a die with a shape to givea sheet material a warp in a direction opposite to a U-bend to beapplied to the sheet material and carries out a bending process in twosteps by using retortion, thereby reducing a warp. Japanese UnexaminedPatent Application Publication No. 2006-15404 (Patent Literature 2)bends a Z-shaped material or a hat channel material with a die, conductsretortion, and through these two steps, reduces a warp.

The Patent Literature 1, however, needs a special die, is unable toflexibly handle various sizes of sheet materials, and complicates theshape of a processed sheet material.

The Patent Literature 2 carries out a bending process in two steps toelongate a processing time and is unable to deal with special shapes.

The inventors of the present invention have studied a mechanism of alongitudinal warp in a bending process such as a V-bending process,clarified the occurrence and suppression of a warp in the bendingprocess, and filed Japanese Patent Application No. 2011-5649 andJapanese Patent Application No. 2011-242372 that is a domestic priorityclaim application based on the Japanese Patent Application No.2011-5649. These applications pressurize a cut edge of a sheet materialto increase or decrease residual stress caused in the sheet material atthe time of cutting the sheet material, thereby suppressing a warp.

SUMMARY OF INVENTION Problems to be Solved by Invention

Bending a sheet material according to the proposals of the inventors ofthe present invention needs, in addition to a bending machine forbending the sheet material, a press machine for pressing a cut edge ofthe sheet material and necessitates pressing an end face of the sheetmaterial by the press machine, and thereafter, moving the sheet materialto the bending machine. This makes the handling of the sheet materialtroublesome and time and labor consuming.

To cope with this, pressing an end face of a sheet material and bendingthe same may be conducted by a single bending machine. This, however,requires a die for pressing the end face of the sheet material and a diefor bending the sheet material must be replaced with each otheraccording to a process to be carried out on the sheet material. Thiscauses problems of increasing work steps and making the handling of thesheet material troublesome.

Using a bending machine to press an end face of a sheet material in athickness direction for a predetermined width (for reducing a warp to becaused in a bending process) raises a problem that, depending on apressing mode, the part of the sheet material to be pressed isincorrectly pressed.

Means to Solve Problems

The present invention is able to provide a sheet metal processingapparatus, a press die, and a die setting body (for supporting a die seton the processing machine), capable of easily handling a sheet materialand improving workability.

Also, the present invention is able to provide a processing apparatus, apress die, and a die setting body, capable of correctly pressing a sheetmaterial so as to minimize a warp that may occur when bending the sheetmaterial.

A first technical aspect of the present invention provides a sheetmaterial processing apparatus having a pressurizing part to pressurize asheet material and a supporting part to support the sheet materialpressurized by the pressurizing part. The processing apparatus includesan end face pressing upper press die that receives a pressurizing forcefrom the pressurizing part, an end face pressing lower press die that isarranged on the supporting part and faces the end face pressing upperpress die so that an end face of the sheet material is inserted betweenthe end face pressing upper and lower press dies, an end face pressingpart that, with the pressurizing force from the pressurizing part movingthe end face pressing upper press die toward the end face pressing lowerpress die, presses the end face of the sheet material along a bend lineof the sheet material to be bent, and an end face pressing widthadjusting part that sets a pressing width of the end face of the sheetmaterial so that, when the end face pressing part presses the end face,a contact face of the end face of the sheet material comes in front of,in a direction in which the sheet material is inserted between the endface pressing upper and lower press dies, a pressurizing center of thepressurizing force applied from the pressurizing part to the end facepressing upper press die.

A second technical aspect of the present invention provides a press dieinstalled on and used by a processing apparatus that employs a punch, adie, and a pressurizing part to bend a sheet material. The press dieincludes an end face pressing upper press die that receives apressurizing force from the pressurizing part that drives the punchtoward the die, an end face pressing lower press die that is arranged toface the end face pressing upper press die so that an end face of thesheet material is inserted between the end face pressing upper and lowerpress dies, an end face pressing part that, with the pressurizing forcefrom the pressurizing part moving the end face pressing upper press dietoward the end face pressing lower press die, presses the end face ofthe sheet material along a bend line of the sheet material to be bent,and an end face pressing width adjusting part that sets a pressing widthof the end face of the sheet material so that, when the end facepressing part presses the end face, a contact face of the end face ofthe sheet material comes in front of, in a direction in which the sheetmaterial is inserted between the end face pressing upper and lower pressdies, a pressurizing center of the pressurizing force applied from thepressurizing part to the end face pressing upper press die.

A third technical aspect of the present invention provides a die settingbody installed on and used by a processing apparatus that employs apunch and a die to bend a sheet material. The die setting body includesa die setting part on which the die is set and an end face pressing partthat presses an end face area of the sheet material along a bend linealong which the sheet material is to be bent by the punch and the dieset on the die setting part. The end face pressing part is positionedopposite to an apparatus base of the processing apparatus with apressurizing center of the punch and die being interposed between theend face pressing part and the apparatus base.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side view generally illustrating a bending apparatusaccording to a first embodiment of the present invention.

FIG. 2 is a perspective view illustrating a bending part of the bendingapparatus.

FIG. 3 is a perspective view illustrating a backside of the bending partof the bending apparatus.

FIG. 4 is a perspective view illustrating a height adjusting mechanismof an end face pressing part.

FIG. 5 is a side view illustrating the height adjusting mechanism.

FIG. 6 is a perspective view illustrating the height adjusting mechanismwith an end face pressing lower press die being omitted.

FIG. 7 is a front view illustrating an action of the height adjustingmechanism.

FIG. 8 is a side view illustrating a pressing width adjusting mechanism.

FIG. 9 is a plan view illustrating the pressing width adjustingmechanism.

FIG. 10 is a perspective view illustrating the pressing width adjustingmechanism.

FIG. 11 is a perspective view illustrating the pressing width adjustingmechanism.

FIG. 12 is a perspective view illustrating a sheet material causing awarp after a bending process.

FIG. 13 is a front view generally illustrating a bending apparatusaccording to a second embodiment of the present invention.

FIG. 14 is a side view seen from an arrow XIV of FIG. 13, generallyillustrating the bending apparatus and corresponding to FIG. 2.

FIG. 15 is a perspective view illustrating a die setting body installedon the bending apparatus with a cover plate being removed.

FIG. 16 is a sectional view along XVI-XVI of FIG. 15.

FIG. 17 is a simplified view of FIG. 16.

FIG. 18 is a simplified sectional view along XVIII-XVIII of FIG. 15.

FIG. 19 is a view illustrating a state that a die holder (upper pressdie) is lowered from the state of FIG. 17 and a lower press die and theupper press die hold and press an end face of a sheet material.

FIG. 20 is a view illustrating a state that the lower press die is movedbackward from the state of FIG. 17, the die holder (upper press die) islowered, and the end face of the sheet material is not held or pressed.

FIG. 21 is a view illustrating a state that a stopper (stopper support)is moved to a rear end from the state of FIG. 18.

FIG. 22 is a view illustrating a state that a sheet material to behemmed is set on the lower press die in the state of FIG. 21.

FIG. 23 is a view illustrating a state that the die holder (upper pressdie) is lowered from the state of FIG. 22 and the lower and upper pressdies hold, press, and hem an end face of the sheet material.

FIG. 24 is a view illustrating a state that a die (the die holder) islowered from the state of FIG. 17, a sheet material is set on the die,and a punch is lowered to hold and bend the sheet material against thedie.

FIG. 25 is an enlarged view illustrating a part XXV of FIG. 24.

FIG. 26 is a perspective view illustrating a part for pressing a sheetmaterial of a bending apparatus according to a third embodiment of thepresent invention with an end face pressing upper press die beinglifted.

FIG. 27 is a view illustrating a state that the end face pressing upperpress die is lowered from the state of FIG. 26, to press an end face ofa sheet material (to reduce a warp to be caused when bending the sheetmaterial).

FIG. 28 is a view illustrating a state that the end face pressing upperpress die is lowered from the state of FIG. 26, to hem the sheetmaterial.

FIG. 29 is a view seen from an arrow XXIX of FIG. 26.

FIG. 30 is a side view illustrating behaviors of the end face pressingupper and lower press dies during the pressing process of FIG. 27.

MODE OF IMPLEMENTING INVENTION First Embodiment

The present invention will be explained in detail according to theillustrated embodiments. FIG. 1 to 12 illustrate a sheet materialbending apparatus (sheet material processing apparatus) 1 according tothe first embodiment of the present invention, in which FIG. 1 is a sideview generally illustrating the apparatus and FIGS. 2 and 3 areperspective front and backside views illustrating a bending part 2.FIGS. 4 to 7 illustrate an end face pressing part 3 and a heightadjusting mechanism 41 of the end face pressing part 3, FIGS. 8 to 11illustrate a pressing width adjusting mechanism 51 of the end facepressing part 3, and FIG. 12 illustrates press control of an end face ofa sheet material.

The sheet material bending apparatus (for example, a press brake) 1 hasa function of bending a metallic sheet material (sheet work) W, and inaddition, a function of pressing an end face of the sheet material W toadjust residual stress caused by cutting the sheet material W. For this,as illustrated in FIG. 1, the bending apparatus 1 includes the bendingpart 2 for bending, for example, V-bending the sheet material W, the endface pressing part 3 for pressing one end face of the sheet material Wbefore bending the sheet material, and an apparatus base 5 forintegrally supporting them.

The apparatus base 5 includes an upper base 5 a and a lower base 5 bthat are connected to each other so that they vertically face each otherto form an elongated U-shape (or C-shape) when seen from a side. Thebending part 2 is arranged on the upper base 5 a and the end facepressing part 3 is arranged on the lower base 5 b so that the end facepressing part 3 is under the bending part 2 and faces the same. In thebending apparatus 1, the end face pressing part 3 presses the one endface of the sheet material W cut by, for example, laser or shearing,thereby increasing or decreasing residual stress. After the one end faceis pressed, the sheet material W is bent by the bending part 2. Thisresults in reducing an occurrence of a warp of the sheet material W tobe bent.

As illustrated in FIG. 1, the bending part 2 has a punch-side member 11arranged on the upper base 5 a, a die-side member 12 arranged under thepunch-side member 11, and a bending driver (driver) 13 made of ahydraulic cylinder to drive the punch-side member 11. The hydrauliccylinder may be another actuator such as a servo motor. The bendingdriver 13, i.e., the hydraulic cylinder is vertically oriented and isattached to the upper base 5 a of the apparatus base 5, so thatextending and contracting actions thereof vertically move the punch-sidemember 11 toward and away from the die-side member 12. Instead of or inaddition to vertically moving the punch-side member 11, the die-sidemember 12 may be configured to vertically move.

The punch-side member 11 is arranged under the bending driver 13 and hasa punch 14 for pressing the sheet material W, a punch holder 15 to whichthe punch 14 is attached, and an upper table 16 to which the punchholder 15 is attached. The upper table 16 is connected to the bendingdriver 13 so that driving the bending driver 13 results in verticallymoving the upper table 16, punch holder 15, and punch 14 to press thesheet material W.

The die-side member 12 faces the punch 14 and has a die 17 for receivingthe sheet material W pressed by the punch 14, a die holder (first dieholder) 18 for supporting a lower part of the die 17, and a lower table(second die holder) 21. The lower table 21 and die holder 18 sandwichand hold the die 17. Protruding from an upper part of the lower table 21is a hold piece 21 a that faces the die holder 18. The die 17 has a leg17 a that is held between the die holder 18 and the hold piece 21 a. Inthis state, the die holder 18 is tightened with a screw to hold the die17 between the die holder 18 and the lower table 21.

The lower table 21 is attached to a base frame 25 that is fixed to thelower base 5 b of the apparatus base 5, so that the die-side member 12as a whole is supported by the base frame 25. The base frame 25 has anL-shape in a side view and includes an upright side wall 25 a. The lowertable 21 is vertically movably attached to the side wall 25 a of thebase frame 25. As illustrated in FIG. 3, the side wall 25 a of the baseframe 25 has a plurality of vertically elongated long holes 26 atpredetermined intervals. A back face of the lower table 21 is providedwith a plurality of screws 27 that pass through the long holes 26,respectively. In this way, the lower table 21 is vertically movablyattached to the base frame 25. With this configuration, the punch 14 ismoved toward the die 17 to press the sheet material W against the die17. Pressure of the punch 14 provides a downward moving force onto thelower table 21, and therefore, the lower table 21 moves in the samedirection. Arranged inside the side wall 25 a of the base frame 25 arereturn springs 28 corresponding to the screws 27. The return springs 28are compressed by the downward movement of the lower table 21 andreaction force thereof returns the lower table 21 to an original heightposition.

The bending part 2 bends the sheet material W into, for example, aV-shape and the bending of the sheet material W is conducted along apressing center 7 (refer to FIG. 1) of the punch 14 and die 17.

The end face pressing part 3 has an end face pressing lower press die 31arranged to face the lower table 21. The end face pressing lower pressdie 31 presses the end face of the sheet material W along a bend line ofthe sheet material W to be bent. The end face side of the sheet materialW is placed on the end face pressing lower press die 31. In this state,the punch 14 is moved toward the die 17 to move the lower table 21 inthe same direction. The movement of the lower table 21 holds the sheetmaterial W between the lower table 21 and the end face pressing lowerpress die 31, thereby pressing the vicinity of the end face 19 of thesheet material W. To achieve this, a lower end of the lower table 21corresponding to the end face pressing lower press die 31 is an end facepressing upper press die 32.

According to this configuration, the bending part 2 for bending thesheet material W and the end face pressing part 3 for pressing the endface of the sheet material W to suppress a warp of the sheet material Ware arranged on the single apparatus base 5. Accordingly, the singleapparatus is able to press the end face of the sheet material W and bendthe sheet material W. This configuration easily handles the sheetmaterial W, thereby improving workability. Pressing the end face 19 ofthe sheet material W to control residual stress of the sheet material Wis carried out by using the drive force of the bending driver 13 of thebending part 2. This necessitates no separate driving source forpressing the end face 19 of the sheet material W, thereby simplifyingthe apparatus and saving energy.

As illustrated in FIG. 2, the end face pressing lower press die 31 has aplurality of fixed dies 33 and a plurality of movable dies 35. The fixeddies 33 are fixed in their height positions and are arranged on the baseframe 25. The movable dies 35 are arranged adjacent to the fixed dies 33and their height positions are changeable relative to the fixed dies 33.Changing the height positions of the movable dies 35 is carried out by aheight adjusting mechanism 41.

As illustrated in FIGS. 4 to 6, the height adjusting mechanism 41 has aheight adjust drive source 42 arranged behind the base frame 25 and ashim 43 arranged above the base frame 25. The height adjust drive source42 may be a cylinder or a motor. According to this embodiment, it is acylinder. The shim 42 is a flat plate and is arranged above the baseframe 25 to face a lower face of the movable die 35. The lower face ofthe movable die 35 opposing the shim 43 is a stepped face including ahigher plane 35 a and a lower plane 35 b.

The flat shim 43 is movable above the base frame 25 in a directiontoward or away from the die-side member 12. To realize this movement,the height adjust drive source 42 has a piston 42 a whose front end isprovided with a connection bracket 44. To a front end of the connectionbracket 44, the shim 43 is attached. The connection bracket 44 slideswhen driven by the height adjust drive source 42 in the above-mentioneddirection toward or away from the die-side member 12.

When this movement causes the shim 43 to face the higher plane 35 a, alarge gap is created between the shim 43 and the higher plane 35 a ofthe movable die 35, and therefore, the movable die 35 can be lowered bythe large gap. In the lowered state, the movable die 35 is irrelevant tothe pressing of the sheet material W. This state is illustrated in FIG.7 in which the movable dies 35 are lower than the fixed dies 33. If, inthis state, the punch 14 is lowered to lower the lower table 21, the endface pressing upper press die 32 of the lower table 21 and the fixeddies 33 press the end face of the sheet material W. The movable dies 35,however, conduct no pressing. When the shim 43 is moved to face thelower plane 35 b to approach the lower plane 35 b, a top face of eachmovable die 35 agrees with that of the fixed die 33 and stops thereat.In this lifted state of the movable dies 35, the movable dies 35 andfixed dies 33 together press the sheet material W.

By changing the height position of each movable die 35, the end facepressing lower press die 31 is able to partially press the end face ofthe sheet material W. It is possible, therefore, to press necessaryparts of the sheet material W.

The bending apparatus 1 according to the present embodiment is able toadjust a pressing width of the end face of the sheet material W. Thisadjustment is carried out by the pressing width adjusting mechanism 51.

As illustrated in FIGS. 8 to 11, the pressing width adjusting mechanism51 has end face stopper bars 53 arranged on the end face pressing lowerpress die 31 and a back gauge (not illustrated) to move the end facepressing lower press die 31.

The end face stopper bar 53 is arranged on the fixed die 33 of the endface pressing lower press die 31 and is inserted between the fixed die33 and the lower table 21 of the die-side member 12. Inserted betweenthe fixed die 33 and the lower table 21, the end face stopper bar 53faces the end face 19 of the sheet material W set on the end facepressing lower press die 31 (refer to FIG. 1) and comes into contactwith the end face 19 of the sheet material W. This results in stoppingthe sheet material W on the end face pressing lower press die 31.Accordingly, dimensions of a pressed face at the end face 19 of thesheet material W are adjustable.

As illustrated in FIG. 11, the present embodiment provides the fixed die33 with a bar accommodation groove 56 into which the end face stopperbar 53 is received. The bar accommodation groove 56 contains acoil-shaped support spring 57 that supports the end face stopper bar 53.In such a support structure, the lower table 21 descends to come intocontact with the end face stopper bar 53 and the end face stopper bar 53compresses the support coil spring 57 and enters into the baraccommodation groove 56. When the lower table 21 ascends, the torque ofthe compressed support spring 57 pushes the end face stopper bar 53 outof the bar accommodation groove 56 so that the end face stopper bar 53appears from the top face of the fixed die 33. In this way, the end facestopper bar 53 is able to appear and disappear from the fixed die 33.

The back gauge serves as a mover to move the fixed dies 33 in adirection orthogonal to the direction in which the punch 14 is pressedto the die 17. The back gauge is, for example, a cylinder to whichconnection blocks 59 are connected. Each connection block 59 is attachedto the fixed die 33. In this configuration, a pressing operation of theback gauge advances each fixed die 33 in the direction orthogonal to thedirection in which the punch 14 presses the die 17. As illustrated inFIGS. 9 to 11, a back face of the fixed die 33 is in contact with areturn spring 60 that is compressed when the fixed die 33 advances. Whenthe back gauge stops, the advanced fixed die 33 returns to an originalposition due to reaction of the bent return spring 60.

The pressing width adjusting mechanism 51 of the above-mentionedconfiguration moves the fixed dies 33 in the direction orthogonal to thepressing direction of the punch 14 toward the die 17, thereby adjustinga contact position of the end face stopper bars 53 with respect to theend face of the sheet material W. Accordingly, a pressing dimension(width in an insertion direction) of the end face 19 of the sheetmaterial W to be pressed by the lower table 21 (the end face pressingupper press die 32) and the end face pressing lower press die 31 isadjustable according to residual stress of the sheet material W.

Namely, it is possible to easily control the residual stress of thesheet material W.

To adjust the pressing width of the end face of the sheet material Wwith the pressing width adjusting mechanism 51, the end face 19 of thesheet material W is inserted between the lower table 21 and the end facepressing lower press die 31 toward the die-side member 12. Thereafter,the bending driver 13 is driven to move (lower) the punch 14 toward thedie 17 to lower the lower table 21 under the die 17 so that the end faceside (an edge area adjacent to the end face 19) of the sheet material Wis pressed between the end face pressing upper press die 32 of the lowertable 21 and the end face pressing lower press die 31.

As illustrated in FIG. 1, the part of the sheet material W to be pressed(the part held between and pressed by the end face pressing upper pressdie 32 and the fixed dies 33 and movable dies 35) is positioned on theinsertion side of the sheet material W from the pressing center 7 of thepunch 14 and die 17. The pressing width adjusting mechanism 51 may movethe fixed dies 33 to move the end face stopper bars 53 relative to thepressing center, so that the pressed width of the sheet material W isproperly adjusted. The pressed part of the sheet material W may bepositioned so that part thereof is beyond the pressing center 7 in theinsertion direction of the sheet material W.

The embodiment mentioned above is capable of precisely setting theposition of the end face 19 of the sheet material W, i.e. the positionof an area around the end face of the sheet material W to be pressed,with the use of the pressing width adjusting mechanism 51. Accordingly,the embodiment is capable of properly dealing with the problem ofresidual stress of the sheet material.

As explained above, the sheet material bending apparatus 1 according tothe present embodiment has the bending part 2 for bending the sheetmaterial W and the end face pressing part 3 for pressing an end face ofthe sheet material W to suppress a warp, the parts 2 and 3 beingarranged on the single apparatus base 5. Accordingly, the singleapparatus can carry out an end-face pressing process and a bendingprocess on the sheet material W, to make the handling of the sheetmaterial easier and improve workability.

The pressing width adjusting mechanism 51 having the end face stopperbars 53 to be brought into contact with an end face of the sheetmaterial W is able to adjust a pressing width of the end face 19 of thesheet material W. Namely, press dimensions around the end face of thesheet material W are adjustable according to residual stress of thesheet material W to easily control the residual stress of the sheetmaterial W.

Pressing the end face of the sheet material W by the end face pressingpart 3 to control the residual stress of the sheet material W isachieved by using the driving force of the bending driver 13 of thebending part 2 for bending the sheet material W. This eliminates a needof an additional drive source for pressing the end face of the sheetmaterial W, simplifies the structure of the apparatus, and saves energy.

Second Embodiment

A processing apparatus (sheet material bending apparatus) 101 accordingto the second embodiment is configured similar to the bending apparatus1 according to the first embodiment. It has a function of bending ametallic sheet material (sheet work) W and a function of pressing an endface of the sheet material W to adjust residual stress caused bycutting. It operates like the bending apparatus 1 of the firstembodiment and provides like effects.

As illustrated in FIGS. 13, 14, 19, 24, and the like, the bendingapparatus (for example, a press brake) 101 has a bending part 103 forbending, for example, V-bending the sheet material W, an end facepressing part 105 for pressing one end face of the sheet material Wbefore bending the sheet material W, and a C-shaped apparatus base 107for supporting them together.

As illustrated in FIG. 14, the apparatus base 107 includes an upper base107 a and a lower base 107 b that are connected to each other so thatthey vertically face each other to form a C-shape when seen from a side.The bending part (bending press part) 103 is arranged on the upper base107 a and the pressing part (end face pressing part) 105 is arranged onthe lower base 107 b so that the end face pressing part 105 is under thebending part 103 and faces the same.

In the bending apparatus 101, the end face pressing part 105 presses anend face of the sheet material W cut by, for example, laser or shearing,thereby increasing or decreasing residual stress. After the end face orboth end faces are pressed, the sheet material W is bent by the bendingpart 103. This results in suppressing an occurrence of a warp andbending the sheet material W with a minimized boat warp.

The bending part 103 has a punch-side member 109 arranged on the upperbase 107 a, a die-side member 111 arranged on the lower base 107 b underthe punch-side member 109, and a bending driver (driver) 113 made of ahydraulic cylinder 163 or a servo motor to drive the punch-side member109. The hydraulic cylinder 163 of the bending driver 113 is verticallyoriented and is attached to the upper base 107 a of the apparatus base107, so that extending and contracting actions thereof vertically movethe punch-side member 109 toward and away from the die-side member 111.

Changing pressure of hydraulic oil supplied to the hydraulic cylinder163 results in adjusting thrust of the punch-side member 109. Instead ofor in addition to vertically moving the punch-side member 109, thedie-side member 111 may be configured to vertically move.

The punch-side member 109 is arranged under the bending driver 113 andhas a punch 115 for pressing the sheet material W, a punch holder 117 towhich the punch 115 is integrally attached, and an upper table 119 towhich the punch holder 117 is integrally attached. The upper table 119is connected to the bending driver 113 so that driving the bendingdriver 113 results in vertically moving the upper table 119, punchholder 117, and punch 115 to press the sheet material W.

The die-side member 111 faces the punch 115, and as illustrated in FIGS.16, 17, 24, and the like, has a die 121 for receiving the sheet materialW pressed by the punch 115, a die holder (die hold body) 125 forsupporting a lower part of the die 121, and an upper press die (an endface pressing upper press die; a die holder support member) 127.

The die holder 125 is integrally provided with the die 121 and upperpress die 127. The die-side member 111 is attached to a base frame 123that is fixed to the lower base 107 b (a lower table 159) of theapparatus base 107. Namely, the die-side member 111 (the die holder 125,die 121, and upper press die 127) is supported by the base frame 123 andis vertically movable relative to the base frame 123.

The die-side member 111 is upwardly pushed by a push member such as acylinder (for example, a pneumatic cylinder) 129. When compressed air isfed into a lower cylinder chamber of the pneumatic cylinder 129, thedie-side member 111 ascends as illustrated in FIG. 17. If pressure ofthe compressed air fed into the pneumatic cylinder 129 is constant, thedie-side member 111 is always pushed upward under the constant pushingforce without regard to the position thereof.

When the compressed air into the lower cylinder chamber of the pneumaticcylinder 129 is stopped, i.e. when the lower cylinder chamber and anupper cylinder chamber of the pneumatic cylinder 129 are opened to theatmosphere, the die-side member 111 descends due to its own weight.

The die-side member 111 may forcibly be lowered by feeding compressedair into the upper cylinder chamber of the pneumatic cylinder 129 andopening the lower cylinder chamber to the atmosphere.

Instead of the cylinder, a resilient body such as a compression coilspring may be employed to upwardly bias the die-side member 111 like thebending apparatus 1 of the first embodiment. It is possible that thebending apparatus 1 of the first embodiment employs a cylinder toupwardly bias the die-side member 12.

Instead of the cylinder or the resilient body such as the compressioncoil spring, an actuator such as a servo motor may be employed tovertically move and optionally position the die holder 125 and end facebiasing upper press die 127.

The bending part 103 bends the sheet material W into, for example, aV-shape and the bending of the sheet material W is conducted along apressing center 131 (refer to FIG. 24 and the like) of the punch 115 anddie 121.

The end face pressing part 105 has an end face pressing lower press die(a lower press die) 135 arranged to face the upper press die 127. Thelower press die 135 presses the end face of the sheet material W along abend line of the sheet material W to be bent.

The end face side of the sheet material W is placed on the end facepressing lower press die 135. In this state, the punch 115 is moved(downward) toward the die 121 to move the die holder 125 and upper pressdie 127 in the same direction. Due to this movement, the sheet materialW is held between the upper press die 127 and the lower press die 135and the end face of the sheet material W is pressed (refer to FIG. 19).

The lower press die 135 is divided into a plurality of press dies 137(137A, 137B, 137C) and 139 (139A, 139B, 139C, 139D, 139E, 139F) (referto FIG. 15 and the like) to press the end face of the sheet material Wagainst the die-side member 111 (the upper press die 127), incorporation with the end face pressing upper press die 127 of thedie-side member 111.

Among the divided press dies 137 and 139, the press dies 137A, 137B, and137C, for example, are able to selectively press (pressurize) the sheetmaterial W against the die-side member 111.

The selective pressing is carried out to secure pressing force of theend face pressing part 105 applied to the sheet material W even whenpressing force (pressurizing force) of the bending driver 113 isinsufficient.

In more detail, pressing the end face of the sheet material W by the endface pressing part 105 (in a thickness direction of the sheet materialW) is carried out by using pressing force of the bending apparatus 101(the hydraulic cylinder 163 of the bending driver 113). It is assumedthat the end face pressing lower press die 135 is divided into threepress dies (a first press die 137A, a second press die 137B, and a thirdpress die 137C) (refer to FIGS. 13 and 15).

The length of the first press die (divided die) 137A (the lengthincluding the press dies 139A and 139B), the length of the second pressdie 137B (the length including the press dies 139C and 139D), and thelength of the third press die 137C (the length including the press dies139E and 139F) are equal to one another and are each about 500 mm. Thefirst to third press dies 137A, 137B, and 137C are connected to eachother in the length direction to make the length (in the left-rightdirection) of the end face pressing lower press die 135 to 1500 mm. Thelengths of the press dies (divided dies) 139A to 139F are equal to oneanother and are each about 50 mm, which is sufficiently shorter than thelength of the press die 137.

The length of an end face of the sheet material W along a bend line isslightly shorter than 1500 mm. A 500-millimeter end part of the end facehaving the length slightly shorter than 1500 mm of the sheet material Wis pressed by the press die 137A and press dies 139A and 139B (the pressdies 139C to 139F can be included in some case). Similarly, a500-millimeter central part of the end face is pressed by the secondpress die 137B and the 500-millimeter remaining part thereof is pressedby the third press die 137C.

The bending apparatus 101 (bending driver 113) is supposed to have amaximum pressing force of 50 t (50000 kgf; about 500 kN). It is supposedthat a pressing force of 60 t, which is greater than the maximumpressing force of 50 t, is required if simultaneously pressing the endface of the sheet material W (made of, for example, SPCC) having thelength slightly shorter than 1500 mm along the bend line with the use ofthe first to third press dies 137A to 137C and the press dies 139A to139F to contain a boat warp caused when bending the sheet materialwithin an allowable range.

In this case, the first press die 137A is first selected and the500-millimeter end part of the sheet material W is pressed only by thefirst press die 137A (including the press dies 139A to 139F) under apressing force of about 20 t. Thereafter, the second press die 137B isselected and the 500-millimeter central part of the sheet material W ispressed only by the second press die 137B (including the press dies 139Ato 139F) under a pressing force of about 20 t. Thereafter, the thirdpress die 137C is selected and the 500-mm remaining part of the sheetmaterial W is pressed only by the third press die 137C (including thepress dies 139A to 139F) under a pressing force of about 20 t.

The selection mentioned above is realized by separately moving the pressdies 137 and 139 in a direction (an orthogonal direction; a front-reardirection) intersecting with the driving (moving) direction (thedirection to press the sheet material W; a vertical direction) in whichthe punch-side member 109 (punch 115) is moved toward the die-sidemember 111 (die 121).

If, for example, the press die 137 is moved backward, the press die 137comes obliquely under the punch-side member 109 (punch 115) asillustrated in FIG. 20. If the upper press die 127 descends in thisstate, the sheet material W is not held between or not pressed by theupper press die 127 and press die 137.

If the press die 137 is moved forward, the press die 137 comes justunder the punch-side member 109 (punch 115) as illustrated in FIG. 19.If the upper press die 127 is lowered in this state, the sheet materialW is held between and pressed by the upper press die 127 and press die137.

The press die 137A illustrated in FIG. 15 is divided into a plurality of(for example, three) press dies. These press dies are connected togetherwith a connection member 141 (141A) and are moved in the front-reardirection by an actuator such as a pneumatic cylinder (not illustrated).Similarly, press dies 137B are connected together with a connectionmember 141 (141B) and are moved in the front-rear direction. Also, pressdies 137C are connected together with a connection member 141 (141C) andare moved in the front-rear direction.

Among the press dies 137 and 139, the press dies (stopper supports) 139(139A to 139F illustrated in FIG. 15) are moved and positioned in thefront-rear direction by a back gauge 143 of the bending apparatus 101(refer to FIGS. 13 and 14).

The press die 139 has a stopper (contact bar) 145 to which the sheetmaterial W is pushed (brought into contact) (refer to FIG. 18 and thelike). An end face of the sheet material W is pressed to position thesheet material W and determine a pressing width (a dimension L1 in FIG.19) of the sheet material W to be pressed by the end face pressing part105.

The bending apparatus 101 has, for example, two back gauges 143 that areseparately moved and positioned.

There are arranged at least two (six in FIG. 15) stopper supports (pressdies) 139. Among the plurality of stopper supports 139, two are inintegrated with the two back gauges 143, respectively.

The stopper supports 139 to be engaged with the back gauges 143 areproperly selected according to the length of an edge of the sheetmaterial W in a length direction of the bend line along which the punch115 and die 121 bend the sheet material W.

The two stopper supports 139 engaged with the two back gauges 143 areseparately moved and positioned with the respective back gauges 143 inthe front-rear direction.

As is already understood, the stopper supports 139, stoppers 145, backgauges 143, and the like form the pressing width adjusting mechanism ofthe bending apparatus 101.

The bending apparatus 1 according to the first embodiment similarly usesback gauges to position the press dies (stopper supports; contact barsupports).

The stopper 145 appears and disappears from a face (sheet materialpressing face) 149 of the stopper support 139 that presses the sheetmaterial W. The stopper 145 is pushed by a resilient body such as acompression coil spring 151 so that the stopper 145 protrudes upwardfrom the sheet material press face 149. When the sheet material W ispositioned, the stopper 145 protrudes upward from the sheet materialpress face 149. When the sheet material W is pressed by the end facepressing upper press die 127 and end face pressing lower press die 135,the stopper 145 is pushed by the end face pressing upper press die 127and is moved into the stopper support 139 (the press die of the end facepressing lower press die 135).

The bending apparatus 101 (also the bending apparatus 1 of the firstembodiment) has a hemming part 153 to hem the sheet material W (refer toFIGS. 22 and 23).

The hemming part 153 is included by (serves also as) the end facepressing part 105.

The die-side member 111 having the die holder 125 and upper press die127, the base frame 123, the lower press die 135, and the like form adie setting body (die setter) 155.

As is already understood, the die setting body 155 is installed on andused by the bending apparatus 101 (also the bending apparatus 1 of thefirst embodiment) that employs the punch 115 and die 121 to carry out abending process and the like on the sheet material W.

The die setting body 155 has a die setting part 157, the end facepressing part 105, and the hemming part 153. On the die setting part157, the die 121 is arranged. It may be configured to set the punch 115instead of the die 121.

As mentioned above, the end face pressing part 105 presses the end faceof the sheet material W along a bend line before the sheet material W isbent by the punch 115 and the die 121 set on the die setting part 157.

The end face pressing part 105 is divided into the plurality of pressdies 137 and 139 in the extending direction of the bend line along whichthe sheet material W is bent. When pressing the end face of the sheetmaterial W along the bend line, the divide press dies 137 areselectively used.

As mentioned above, the press die 139 having the stopper 145 is movedand positioned by the back gauge 143 of the bending apparatus 101.

In FIG. 15, three die setting bodies 155A, 155B, and 155C are connectedto one another in a longitudinal direction. The die setting body 155illustrated in FIG. 15 is installed on the bending apparatus 101.

The bending apparatus 101, die setting body 155, and the like will beexplained in more detail.

For the sake of explanation, a horizontal direction (left-rightdirection) is set as an X-axis direction, another horizontal direction(front-rear direction) orthogonal to the X-axis direction as a Y-axisdirection, and a direction (top-bottom direction) orthogonal to the X-and Y-axis directions as a Z-axis direction.

As illustrated in FIGS. 13 and 14, the lower table 159 is integrallyarranged at a front lower part of the apparatus base (frame) 107 of thebending apparatus 101. On a top face of the lower table 159, the diesetting body 155 (155A, 155B, 155C) are successively connected in thelongitudinal direction and extending in the X-axis direction (refer toFIGS. 13 and 15).

Above the die setting body 155 (155A, 155B, 155C), the die 121 (121A,121B, 121C) is integrally arranged. The dies 121A, 121B, and 121C havethe same specifications and are successively connected in thelongitudinal direction and extending in the X-axis direction.

At a front upper part of the apparatus base 107, the upper table 119 isarranged. The upper table 119 is movable in the Z-axis directionrelative to the apparatus base 107.

Integrally arranged through the punch holder 117 on lower face of theupper table 119 is the punch 115 (115A, 115B, 115C). The punches 115A,115B, and 115C have the same specifications and are successivelyconnected in the longitudinal direction and extending in the X-axisdirection (refer to FIG. 13).

The punches 115A, 115B, and 115C arranged on the upper table 119 facethe dies 121A, 121B, and 121C arranged on the lower table 159,respectively.

The bending apparatus 101 (bending apparatus 1) is provided with acontroller 161. Under the control of the controller 161, the upper table119 is moved and positioned in the Z-axis direction by the hydrauliccylinder 163 of the bending driver 113.

With this, the bending part 103 bends the sheet material W, the end facepressing part 105 presses an end face of the sheet material W, and thehemming part 153 hems the sheet material W.

The back gauge 143 is arranged at a central part of the apparatus base107 in the Z-axis direction and behind the lower table 159 in the Y-axisdirection. Under the control of the controller 161, the back gauge 143is moved and positioned in the X-, Y-, and Z-axis directions withrespect to the apparatus base 107.

The die setting body 155A will be explained in detail. The die settingbodies 155B and 155C are configured similar to the die setting body155A, and therefore, explanations thereof are omitted.

As illustrated in FIGS. 17, 21, and the like, the die setting body 155Ahas the base frame 123, die holder 125, upper press die 127, cylinder129, lower press die 135 (press dies 137 and 139), connection member141, and stopper 145.

The base frame 123 has a thin and long parallelepiped shape. Moreprecisely, a section (a sectional plane orthogonal to the longitudinaldirection, i.e., the X-axis direction) of the base frame 123 has arectangular lower base part 165 and a rectangular upper joint part 167.

A width (a dimension in the Y-axis direction) of the upper joint part167 is smaller than a width (a dimension in the Y-axis direction) of thelower base part 165. The upper joint part 167 is positioned at anintermediate part of the lower base part 165 in the Y-axis direction andupwardly protrudes from an upper end of the lower base part 165 in theZ-axis direction.

The die holder 125 is formed in a thin and long parallelepiped shapehaving the same length as the base frame 123 and is positioned at thesame location as the base frame 123 in the X-axis direction(longitudinal direction). More precisely, a section (a sectional planenormal to the longitudinal direction) of the die holder 125 has arectangular upper body part 169 and a rectangular lower protrusion part171.

A width value (a dimension in the Y-axis direction) of the lowerprotrusion part 171 is smaller than a width value (a dimension in theY-axis direction) of the upper body part 169. The lower protrusion part171 is positioned at a rear end of the upper body part 169 in the Y-axisdirection and protrudes from a lower end of the upper body part 169 inthe Z-axis direction.

The die holder 125 has a die setting recess (die) setting groove) 173.The die setting recess 173 is formed along the hole length of the dieholder 125 in the longitudinal direction (X-axis direction). When thedie holder 125 is sectioned, a width value of the die setting recess 173is smaller than a width value of the upper body part 169 and a depthvalue (a dimension in the Z-axis direction) thereof is smaller than aheight value (a dimension in the Z-axis direction) of the upper bodypart 169. The die setting recess 173 is positioned at an intermediatepart of the upper body part 169 in the Y-axis direction and downwardlyrecessed in the Z-axis direction from an upper end of the upper bodypart 169.

A lower part of the die 121 is in the die setting recess 173 so that thedie 121 is integrally arranged on the die holder 125. A length (adimension in the X-axis direction) of the die 121 is equal to the lengthof the base frame 123 and is positioned at the same location as the baseframe 123 in the X-axis direction (longitudinal direction).

The upper press die 127 has a thin and long parallelepiped shape havingthe same length as the base frame 123 and is positioned at the samelocation as the base frame 123 in the X-axis direction (longitudinaldirection). More precisely, a section (a sectional plane orthogonal tothe longitudinal direction) of the upper press die 127 has a rectangularupper recess 175 and a triangular lower chamfered part 177 to generallyform an L-shape.

The upper recess 175 and lower chamfered part 177 extend along the holelength of the upper press die 127 in the longitudinal direction (X-axisdirection). When the upper press die 127 is sectioned, a width value ofthe upper recess 175 is smaller than a width value of the upper pressdie 127 and a depth value (a dimension in the Z-axis direction) thereofis smaller than a height value (a dimension in the Z-axis direction) ofthe upper press die 127. The upper recess 175 is arranged at a rearupper corner of the upper press die 127. The lower chamfered part 177 isarranged at a front lower corner of the upper press die 127.

Two faces (sides) of the upper press die 127 that form a front lowercorner of the upper body part 169 of the die holder 125 are in the upperrecess 175. The two faces of the upper recess 175, i.e., a plainspreading in the X- and Y-axis directions and a plain spreading in theX- and Z-axis directions are in face-to-face contact with front andlower faces of the upper body part 169, respectively. In this way, theupper press die 127 is integrated with the die holder 125.

The die holder 125 and the upper press die 127 arranged thereon define athin and long parallelepiped groove 179 at a lower central part thereof.

This groove 179 receives the upper joint part 167 of the base frame 123so that the base frame 123 engages with the die holder 125 and upperpress die 127. With this, the base frame 123 and the die holder 125 andupper press die 127 form a sliding pair so that the die holder 125 andupper press die 127 move in the Z-axis direction relative to the baseframe 123.

A width (a dimension in the Y-axis direction) of the groove 179 is setto be slightly larger than a width (a dimension in the Y-axis direction)of the upper joint part 167 of the base frame 123.

The base frame 123 incorporates the cylinder 129. The cylinder 129 has acylinder body 181, a piston 183, and a piston rod 185.

The cylinder 129 is at a central part of the base frame 123 in theY-axis direction. In the Z-axis direction, the cylinder body 181 andpiston 183 are positioned at a lower part and the piston rod 185upwardly protrudes. A front end of the piston rod 185 protrudes from anupper end of the base frame 123 (the upper joint part 167) andintegrally engages with the upper body part 169 of the die holder 125.The cylinder body 181 is integral with the base frame 123.

When the upper cylinder chamber of the piston 183 is opened to theatmosphere and compressed air is fed into the lower cylinder chamber ofthe piston 183, the die holder 125, upper press die 127, and die 121 arepositioned to a lifted end as illustrated in FIGS. 17, 18, 21, and 22.

When the upper and lower cylinder chambers of the piston 183 are openedto the atmosphere, the die holder 125, upper press die 127, and die 121descend due to, for example, their own weights (refer to FIGS. 19, 20,24, and the like).

The press die 137 (137A) of the lower press die 135 has a thin and longparallelepiped shape. More precisely, as illustrated in FIG. 17, asectional shape (a sectional plane normal to the longitudinal direction)of the press die 137 is substantially rectangular having an upper frontcut 187.

At a front upper part of the lower base part 165 of the base frame 123,there is a recess 189. In a sectional shape of the base frame 123, therecess 189 is rectangular as illustrated in FIG. 17 and is formed at afront upper corner of the lower base part 165 of the base frame 123.

The press die 137 is in the recess 189. A lower face of the press die137 and a bottom face of the recess 189 are in face-to-face contact witheach other. The press die 137 is moved by an actuator such as apneumatic cylinder (not illustrated) in the Y-axis direction relative tothe base frame 123.

In FIGS. 17, 19, 22, 23, and 24, the press die 137 is at a front movableend, and in FIG. 20, the press die 137 is at a rear movable end.

As illustrated in FIG. 18, the press die 139 (139A, 139B) of the lowerpress die 135 has a sectional shape (a sectional plane normal to theX-axis direction) of L having a lower horizontal part 191 and an upperupright part 193.

A height dimension (a dimension in the Z-axis direction) of the lowerhorizontal part 191 is equal to a height dimension of the press die 137.Formed at a front upper part of the lower horizontal part 191 is a cut195 that is similar to the cut 187.

Formed at an upper part of the lower base part 165 and a lower part ofthe upper joint part 167 of the base frame 123 is a through hole 197passing through the base frame 123 in the front-rear direction. A heightposition of a bottom face of the through hole 197 agrees with a heightposition of a bottom face of the recess 189.

The press die 139 arranged in the through hole 197 has a lower face thatis in face-to-face contact with the bottom face of the through hole 197to form a sliding pair.

Accordingly, when the press dies 137 and 139 are arranged on the baseframe 123, the position of an upper face 203 of the press die 137 agreesin the Z-axis direction with the position of an upper face 201 of thelower horizontal part 191 of the press die 139.

The upper upright part 193 of the press die 139 is integrally engagedwith the back gauge 143, and therefore, the press die 139 is able to bemoved and positioned in the Y-axis direction.

The lower horizontal part 191 of the press die 139 is provided with thestopper 145. The stopper 145 is vertically movable with respect to thelower horizontal part 191 and is able to appear and disappear from theupper face 201 of the lower horizontal part 191.

The stopper 145 is upwardly biased by the compression coil spring 151.If no external force is applied, the stopper 145 protrudes from theupper face 201 of the lower horizontal part 191 (refer to FIG. 18). Whenthe punch 115 is lowered, the stopper 145 is pushed by the upper pressdie 127 and is downwardly moved (refer to FIG. 19 and the like).

To press the sheet material W to reduce a boat warp or to bend the sheetmaterial W, the press die 139 (139A to 139F) is positioned in the Y-axisdirection as illustrated in FIG. 18. Namely, the stopper 145 isbackwardly spaced by a proper dimension L1 from a front end of a lowerface 199 of the upper press die 127. The dimension L1 is a pressingwidth of the sheet material W.

To carry out a hemming process, the press die 139 is positioned at arear end as illustrated in FIG. 21. At this time, the stopper 145 is inthe through hole 197 of the base frame 123.

In each of the cases illustrated in FIGS. 18 and 21, the upper face 201of the lower horizontal part 191 of the press die 139 partly holds andpresses the sheet material W, and therefore, faces the lower face 199 ofthe upper press die 127.

In the die setting body 155A, the press dies 137A, 139A, 137A, 139B, and137A are arranged in this order from the left to the right in the X-axisdirection.

As illustrated in FIG. 13, the die setting bodies 155A, 155B, and 155Care arranged in this order from the left to the right in the X-axisdirection. Then, from the left to the right, the press dies 137A, 139A,137A, 139B, 137A, 137B, 139C, 137B, 139D, 137B, 137C, 139E, 137C, 139F,and 137C are arranged in this order (refer to FIG. 15).

Illustrated with a reference numeral 205 in FIG. 17 is a guide plate forguiding the sheet material W. The guide plate 205 is integrally arrangedwith the base frame 123 through the connection member 141.

Protruding from a lower end of the base frame 123 is an engagement pin207. With the engagement pin 207 and fastening tools such as bolts, thebase frame 123 (the die setting body 155) is integrally installed on theupper face of the lower table 159.

As is already understood, the punch 115 and the die 121 set on the diesetting body 155 form the bending part 103. The upper press die 127(lower face 199) of the die setting body 155 and the lower press die 135(upper faces 201 and 203) of the die setting body 155 form the end facepressing part 105 and hemming part 153.

Operation of the bending apparatus 101 will be explained.

The length in the X-axis direction of the die setting bodies 155A, 155B,and 155C is supposed to be 1500 mm (500 mm×3). This means that the die121 and punch 115 are able to bend the sheet material W at one time fora length of 1500 mm at the maximum. The length of a bend line of thesheet material W is supposed to be slightly shorter than 1500 mm.

First, a pressing operation for relaxing a boat warp of the sheetmaterial W and a bending operation for bending the sheet material W willbe explained.

In an initial state illustrated in FIGS. 17 and 18, the punch 115 islifted, the die holder 125 and upper press die 127 are positioned at alifted end, the press die 139 of the die setting body 155A, the pressdie 139 of the die setting body 155B, and the press die 139 of the diesetting body 155C are positioned as illustrated in FIG. 18, the pressdie 137A of the die setting body 155A is forwardly positioned asillustrated in FIG. 17, and the press die 137B of the die setting body155B and the press die 137C of the die setting body 155C are backwardlypositioned as illustrated in FIG. 20.

In this initial state, the sheet material W is set on the die settingbody 155 (155A to 155C). In this state, the die setting body 155 (155Ato 155C) and sheet material W positionally agree with each other in theX-axis direction. As illustrated in FIGS. 17 and 18, the sheet materialW is in contact with the stoppers 145 and is thereby positioned in theY-axis direction.

The punch 115 is lowered so that the upper press die 127 of the diesetting body 155A and the lower press die 135 (the press dies 137A,139A, and 139B) of the die setting body 155A press a longitudinal end ofthe sheet material W for a width L1 (refer to FIG. 19).

At this time, the upper press die 127 of the die setting body 155B andthe press dies 139C and 139D of the die setting body 155B, as well asthe upper press die 127 of the die setting body 155C and the press dies139E and 139F of the die setting body 155C press the sheet material Wsimilarly.

Thereafter, the punch 115, die holder 125, and upper press die 127 arepositioned to a lifted end, the press die 137A of the die setting body155A is positioned rearward as illustrated in FIG. 20, and the press die137B of the die setting body 155B is positioned forward as illustratedin FIG. 19.

Thereafter, the punch 115 is lowered so that the upper press die 127 ofthe die setting body 155B and the lower press die 135 (the press dies137B, 139C, and 139D) of the die setting body 155B press a longitudinalcentral part of the sheet material W for the width L1 (refer to FIG.19).

At this time, the upper press die 127 of the die setting body 155A andthe press dies 139A and 139B of the die setting body 155A, as well asthe upper press die 127 of the die setting body 155C and the press dies139E and 139F of the die setting body 155C press the sheet material Wsimilarly.

Thereafter, the punch 115, die holder 125, and upper press die 127 arepositioned to the lifted end, the press die 137 of the die setting body155B is positioned rearward as illustrated in FIG. 20, and the press die137 of the die setting body 155C is positioned forward as illustrated inFIG. 19.

Thereafter, the punch 115 is lowered so that the upper press die 127 ofthe die setting body 155C and the lower press die 135 (the press dies137C, 139E, and 139F) of the die setting body 155C press the otherlongitudinal end of the sheet material W for the width L1 (refer to FIG.19).

At this time, the upper press die 127 of the die setting body 155A andthe press dies 139A and 139B of the die setting body 155A, as well asthe upper press die 127 of the die setting body 155B and the press dies139C and 139D of the die setting body 155B press the sheet material Wsimilarly.

This completes the pressing of the sheet material W for the full lengthof 1500 mm, i.e. for relaxing a boat warp of the sheet material W.

Thereafter, the punch 115, die holder 125, and upper press die 127 arepositioned to the lifted end, the sheet material W is taken out of thedie setting body 155, and the die holder 125 and upper press die 127 arepositioned to a lowered end as illustrated in FIG. 24. When the dieholder 125 and upper press die 127 are at the lowered end, a gap betweenthe lower face 199 of the upper press die 127 and the upper faces 201and 203 of the lower press die 135 is very small (about 0.2 mm) asillustrated in FIG. 25.

This prevents foreign matter such as dust from entering between thelower face 199 of the upper press die 127 and the upper faces 201 and203 of the lower press die 135, so that the sheet material W isprecisely bent.

When the die holder 125 and upper press die 127 are positioned at thelowered end, an upper face of the upper joint part 167 of the base frame123 and a lower face of the upper body part 169 of the die holder 125are in face-to-face contact with each other.

Thereafter, the sheet material W is set on the die 121 and the punch 115is lowered to bend the sheet material W for nearly the whole length of1500 mm at one time.

A hemming operation of the sheet material W will be explained.

In an initial state illustrated in FIG. 21, the punch 115 is lifted, thedie holder 125 and upper press die 127 are positioned to the lifted end,the press die 139 of the die setting body 155A, the press die 139 of thedie setting body 155B, and the press die 139 of the die setting body155C are positioned to the rear end, and the press die 137A of the diesetting body 155A, the press die 137B of the die setting body 155B, andthe press die 137C of the die setting body 155C are positioned forward.

In this initial state, the punch 115 is lowered to bend the sheetmaterial W as illustrated in FIG. 24. This bending is carried out atonce for the length of about 1500 mm. An angle of the bending is about30 degrees.

Thereafter, the punch 115 is lifted, the die holder 125 and upper pressdie 127 are positioned to the lifted end, and the part of the sheetmaterial W bent by about 30 degrees is set between the upper press die127 and the lower press die 135 (refer to FIG. 22).

Thereafter, the punch 115 is lowered so that the upper press die 127 andlower press die 135 hold the part of the sheet material W bent by about30 degrees and the hemming process is carried out (refer to FIG. 23).

When hemming the sheet material W, the state illustrated in FIG. 22 andthe state illustrated in FIG. 23 have the left end of the sheet materialW set at the same position. To reduce moment generated on the diesetting body 155, the position of the stopper 145 may properly bechanged to change the left end position of the sheet material W that isbrought into contact with the stopper 145 (refer to, for example,Japanese Unexamined Patent Application Publication No. 2003-181546).

In the above explanation, the three punches 115 have the samespecifications and the three dies 121 also have the same specifications.The punches 115 and dies 121 may have different specifications. However,the heights of the dies (a pass line of the sheet material W) must beequal to one another.

Each die setting body 155 may differently process the sheet material W.

For example, the die setting body 155A hems the sheet material W and thedie setting bodies 155B and 155C press and bend the sheet material W.

This enables the sheet material W to be differently processed, forexample, bent, hemmed, and the like without changing arrangements.

According to the bending apparatus 101, the press dies 137 and 139 areable to selectively press the sheet material W so that, withoutincreasing the maximum pressing force of the bending driver 113, asufficient pressing force is applicable to the sheet material W and aboat warp occurring on the sheet material W during bending can easily becontained within an allowable range. Accordingly, without using a largebending apparatus having a maximum thrust required, a sufficientpressing force is applicable to the sheet material W.

The bending apparatus 101 realizes such selective pressing byindividually moving the press dies 137 and 139 in the front-reardirection to achieve the selective pressing. This configuration issimple to select proper ones from among the press dies and press a sheetmaterial.

According to the bending apparatus 101, the simple structure using theback gauge 143 can set an area (a width, i.e., the dimension L1 in FIGS.18 and 19) of the sheet material W to press without using separatemechanisms or actuators.

According to the bending apparatus 101, the hemming part 153 is made ofthe end face pressing part 105, and therefore, is able to hem the sheetmaterial W with a simple configuration without preparing a separatehemming part.

Third Embodiment

A bending apparatus (a brake press; a sheet material processingapparatus) 301 according to the third embodiment differs from thebending apparatus 1 of the first embodiment or the bending apparatus 101of the second embodiment in that the third embodiment employs a pressdie 303, which is not used for bending a sheet material W, to (i) pressan end part of the sheet material W for such as adjusting residualstress caused when cutting the sheet material W or reducing a warp to becaused when bending the sheet material W and to (ii) hem (if required)the end part of the sheet material W. The other parts of the bendingapparatus 301 are configured similar to the bending apparatuses 1 and101, to provide similar operations and similar effects.

The sheet material processing apparatus (processing apparatus) 301according to the third embodiment has an apparatus base 302 (refer toFIG. 30( b)) similar to, for example, the apparatus base 107 illustratedin FIG. 14. It also has a pressurizing part (pressurizing means) 305 forpressurizing the sheet material W and a supporting part (receivingmeans) 307 for supporting the sheet material W pressurized by thepressurizing part 305 (refer to FIGS. 26, 27, 29, and the like).

The processing apparatus 301 also has an end face pressing upper pressdie 309, an end face pressing lower press die 311, an end face pressingpart 313, and an end face pressing width adjusting part (end facepressing width adjusting mechanism) 315.

The end face pressing upper press die 309 is configured to receivepressurizing force from the pressurizing part 305. The pressurizing part305 is made of an actuator such as a hydraulic cylinder (similar to thehydraulic cylinder 163 of the processing apparatus 101 of the secondembodiment illustrated in, for example, FIG. 13) arranged on an upperside of the apparatus base 302. The supporting part 307 is formed by alower part of the apparatus base 302.

The end face pressing lower press die 311 is arranged on the supportingpart 307 side (lower side) and faces the end face pressing upper pressdie 309. Between the end face pressing lower press die 311 and the endface pressing upper press die 309, an end face of the sheet material Wis inserted.

In the end face pressing part 313, the pressurizing part 305 provides apressurizing force to move the end face pressing upper press die 309toward the end face pressing lower press die 311. When the end facepressing upper press die 309 is lowered, one end face 319 of the sheetmaterial W to be processed (to be bent) is pressed (pressurized) along abend line of the she t material V (refer to FIGS. 27, 30, and the like).Namely, between the end face pressing upper press die 309 and the endface pressing lower press die 311, i.e., between the pressurizing part305 and the supporting part 307 in the end face pressing part 313, thesheet material W is held by the end face pressing upper press die 309and end face pressing lower press die 311 so that the end of the sheetmaterial W is pressed in a thickness direction.

When the sheet material W is pressed by the end face pressing part 313,the end face pressing width adjusting part 315 sets a pressing width (adimension in the Y-axis direction) at the end face 319 of the sheetmaterial W. With this, the contact face (stopped face) 319 of the sheetmaterial W is positioned in front of (opposite to the C-shaped apparatusbase 302) a pressurizing center (pressing center) 317 of thepressurizing force applied by the pressurizing part 305 to the end facepressing upper press die 309, in terms of an insertion direction (aleft-to-right direction in FIG. 30, i.e., a front-to-rear direction inthe Y-axis direction) in which the sheet material W is inserted intobetween the end face pressing upper press die 309 and the end facepressing lower press die 311 (refer to FIG. 30( b)). Namely, the stoppedface 319 of the sheet material W is slightly in front of thepressurizing center 317 in the Y-axis direction and the whole of thesheet material W is positioned in front of the stopped face 319 in theY-axis direction.

Similar to the processing apparatus 101 of the second embodiment, theend face pressing lower press die 311 is divided in the X-axis directioninto a plurality of press dies 321 (321A to 321I) that are able to pressthe end of the sheet material W against the end face pressing upperpress die 309 (refer to FIG. 26 and the like).

These divided press dies 321 are configured to be selectively used (torealize selective press) when pressing the end face 319 of the sheetmaterial W.

To achieve such selection, each of the press dies 321 is moved in adirection (Y-axis direction) intersecting with a driving direction(Z-axis direction) in which the end face pressing upper press die 309 isdriven toward the end face pressing lower press die 311.

The end face pressing width adjusting part 315 is a press die (321B,321D, 321F, 321H) among the press dies 321, is moved and positioned inthe above-mentioned intersecting direction (Y-axis direction) by a backgauge (not illustrated in FIGS. 26 to 30) of the processing apparatus301, and is provided with a stopper (contact bar) 323 which is arrangedon the press die and to which the sheet material W is pushed.

The press dies 321A, 321C, 321E, 321G, and 321I are moved in the Y-axisdirection by an actuator such as a pneumatic cylinder (not illustrated).

Similar to the processing apparatus 101 of the second embodiment, thestopper 323 is biased upward by a compression coil spring 325 (refer toFIG. 29).

The processing apparatus 301 also has a hemming part 327 (refer to FIG.28) for hemming an end of the sheet material W. The hemming part 327 isincluded by the end face pressing part 313.

As is already understood, the end face pressing upper press die 309, endface pressing lower press die 311, end face pressing part 313, and endface pressing width adjusting part 315 form the press die 303 that isarranged on and used by the processing apparatus (for example, pressbrake) 301.

The processing apparatus 301 employs a punch, a die, and thepressurizing part 305 to bend the sheet material W. When the press die303 is used to press the sheet material W without bending the sheetmaterial W, the punch and die are not used. Instead, the end facepressing upper press die 309 having a flat lower face is used for thepunch and the end face pressing lower press die 311 having a flat upperface is used for the die, as illustrated in FIG. 26.

As mentioned above, the end face pressing lower press die 311 of thepress die 303 is divided in the X-axis direction into the plurality ofpress dies 321 (321A to 321I). When pressing the end face 319 of thesheet material W along a bend line, the divided press dies 321 areselectively used. Each of the press dies 321 is movable in the Y-axisdirection to realize such selection. Among the press dies 321, thoseprovided with the stoppers 323 are moved and positioned in the Y-axisdirection by the back gauge of the processing apparatus 301.

The press die 303 also has the hemming part 327 that is formed by theend face pressing part 313.

According to the processing apparatus 301, the end face pressing part313 presses the sheet material W. At this time, the end face 319 of thesheet material W and the whole of the sheet material W are positionedopposite to the C-shaped apparatus base 302 (refer to FIG. 30).Accordingly, the sheet material W is surely pressed to reduce a warp tobe caused when the sheet material W is bent.

As illustrated in FIG. 30( a), the end face 319 of the sheet material ispressed. At this time, the sheet material W is positioned opposite tothe C-shaped apparatus base 302 with respect to the pressing center 317.The apparatus base 302 and the like are not perfect rigid bodies. Due tothis, moment (refer to an arrow MT in FIG. 30) occurs on the end facepressing upper press die 309 (end face pressing lower press die 311), tocause a slight resilient deformation (deflection) on the apparatus base302 and the like, thereby slightly inclining the end face pressing upperpress die 309 (end face pressing lower press die 311) (refer to FIG. 30(b)). In FIG. 30( b), the inclination of the end face press die 309 isexaggerated.

Due to the slight inclination caused by the moment MT, the end 319 ofthe sheet material W receives a maximum press force larger than thatapplied to the remaining part of the sheet material W. This correctlyand surely presses the sheet material W and surely reduces a boat warpto be caused when the sheet material W is bent.

The stopper 323 provided for each of the press dies 321B, 321D, 321F,and 321H may be integrally formed on the press die so that the stopper323 is immovable in the Z-axis direction, the heights of the stoppers323 being equalized with one another.

In this case, the end face pressing upper press die 309 is provided witha recess (not illustrated) to receive the stopper 222 to prevent thestopper 323 from interfering with the end face pressing upper press die309 when the press die 309 is lowered.

If the thickness of the sheet material W is larger than the protrudingheight of the stopper 323, the end face pressing upper press die 309 maynot be provided with such a recess to receive the stopper 323.

In addition, the press dies 321B, 321D, 321F, and 321H may be fixed inthe Y-axis direction.

At least one of the die setting bodies 121A, 121B, and 121C illustratedin FIG. 13 may be replaced with the press die 303. In this case, passlines (die heights) of them all must be equalized.

According to a technical aspect of the present invention, a sheetmaterial is correctly pressed to reduce a warp to be caused when thesheet material is bent.

According to another technical aspect of the present invention, abending part for bending a sheet material and an end face pressing partfor pressing an end face of the sheet material to suppress a warp of thesheet material are arranged on a single apparatus. The single apparatus,therefore, is capable of carrying out both the end face pressing andbending of a sheet material, thereby realizing the easy handling of thesheet material and improving workability.

(United States Designation)

In connection with United States designation, this international patentapplication claims the benefit of priority under 35 U.S.C. 119(a) toJapanese Patent Application No. 2011-242501 filed on Nov. 4, 2011 andJapanese Patent Application No. 2012-226724 filed on Oct. 12, 2012,disclosed contents thereof being cited herein.

1. A sheet material processing apparatus having a pressurizing part forpressurizing a sheet material and a supporting part for supporting thepressurized sheet material, characterized in that the apparatuscomprises: an end face pressing upper press die that receives apressurizing force from the pressurizing part; an end face pressinglower press die that is arranged on the supporting part and faces theend face pressing upper press die so that an end face of the sheetmaterial is inserted between the end face pressing upper and lower pressdies; an end face pressing part that, with the pressurizing force fromthe pressurizing part moving the end face pressing upper press dietoward the end face pressing lower press die, presses one end face ofthe sheet material along a bend line of the sheet material to be bent;and an end face pressing width adjusting part that sets a pressing widthof the one end face of the sheet material so that, when the end facepressing part presses the one end face, a contact face of the one endface of the sheet material comes in front of, in a direction in whichthe sheet material is inserted between the end face pressing upper andlower press dies, a pressurizing center of the pressurizing forceapplied from the pressurizing part to the end face pressing upper pressdie.
 2. The sheet material processing apparatus according to claim 1,characterized in that: the end face pressing lower press die is dividedinto a plurality of press dies that are able to press the end face ofthe sheet material against the end face pressing upper press die; andthe divided press dies are configured to be selectively used whenpressing the end face of the sheet material.
 3. The sheet materialprocessing apparatus according to claim 2, characterized in that each ofthe press dies is configured to be moved in a direction intersectingwith a direction in which the end face pressing upper press die isdriven toward the end face pressing lower press die, to realize theselective use.
 4. The sheet material processing apparatus according toclaim 3, characterized in that the end face pressing width adjustingpart includes at least one of the press dies that is moved andpositioned by a back gauge of the processing apparatus in theintersecting direction and a stopper that is arranged on the one pressdie and the sheet material is brought into contact with.
 5. The sheetmaterial processing apparatus according to claim 1, characterized inthat the apparatus comprises a hemming part to hem the sheet material.6. The sheet material processing apparatus according to claim 5,characterized in that the hemming part is configured with the end facepressing part.
 7. The sheet material processing apparatus according toclaim 1, characterized in that the apparatus comprises: a drivergenerating the pressurizing force of the pressurizing part; and abending part integrally supported with the end face pressing part andhaving a punch-side member that presses the sheet material with a punchunder the pressurizing force of the pressurizing part and a die-sidemember having a die on the supporting part that supports the sheetmaterial pressed with the punch, the bending part bending the sheetmaterial between the punch and the die.
 8. The sheet material processingapparatus according to claim 7, characterized in that the plurality ofdivided press dies of the end face pressing lower press die includefixed dies having a fixed height position and movable dies arrangedadjacent to the fixed dies and having height positions to be changedwith respect to the height position of the fixed dies, the movable diesbeing provided with a height adjusting mechanism to change the heightpositions of the movable dies.
 9. The sheet material processingapparatus according to claim 7, characterized in that the apparatuscomprises a pressing width adjusting mechanism adjusting a pressingwidth of the sheet material from the one end face of the sheet material,the pressing width adjusting mechanism including an end face stopper barthat is arranged to appear and disappear from the end face pressinglower press die and is inserted between the die-side member and the endface pressing lower press die so that the one end face of the sheetmaterial set on the end face pressing lower press die comes into contactwith the stopper bar and a mover that moves the end face pressing lowerpress die together with the stopper bar in a direction intersecting withthe direction in which the punch presses the die.
 10. The sheet materialprocessing apparatus according to claim 7, characterized in that thedie-side member is moved by a bending force of the driver toward the endface pressing lower press die to press the one end face of the sheetmaterial against the end face pressing lower press die.
 11. The sheetmaterial processing apparatus according to claim 7, characterized inthat the die-side member includes a lower table and a die holder tosupport the die on the lower table, the lower table has the end facepressing upper press die, and the lower table is movable toward the endface pressing lower press die when the driver presses the punch towardthe die, thereby pressing the one end face of the sheet material againstthe end face pressing lower press die.
 12. The sheet material processingapparatus according to claim 8, characterized in that the heightadjusting mechanism moves the movable dies toward or away from thedie-side member, thereby adjusting the height positions of the movabledies.
 13. The sheet material processing apparatus according to claim 7,characterized in that the apparatus comprises a hemming part to hem thesheet material.
 14. The sheet material processing apparatus according toclaim 13, characterized in that the hemming part is configured with theend face pressing part.
 15. A press die installed on and used by aprocessing apparatus that employs a punch, a die, and a pressurizingpart to bend a sheet material, characterized in that the press diecomprises: an end face pressing upper press die that receives apressurizing force from the pressurizing part that drives the punchtoward the die; an end face pressing lower press die that is arranged toface the end face pressing upper press die so that an end face of thesheet material is inserted between the end face pressing upper and lowerpress dies; an end face pressing part that, with the pressurizing forcefrom the pressurizing part moving the end face pressing upper press dietoward the end face pressing lower press die, presses one end face ofthe sheet material along a bend line of the sheet material to be bent;and an end face pressing width adjusting part that sets a pressing widthof the one end face of the sheet material so that, when the end facepressing part presses the one end face, a contact face of the one endface of the sheet material comes in front of, in a direction in whichthe sheet material is inserted between the end face pressing upper andlower press dies, a pressurizing center of the pressurizing forceapplied from the pressurizing part to the end face pressing upper pressdie.
 16. The press die according to claim 15, characterized in that theend face pressing lower press die is divided into a plurality of pressdies in a direction of the bend line of the sheet material to be bent,the divided press dies being configured to be selectively used whenpressing the end face extending along the bend line of the sheetmaterial.
 17. The press die according to claim 16, characterized in thateach of the press dies is configured to be moved in a directionintersecting with a direction in which the pressurizing part drives thepunch toward the die, to realize the selective use.
 18. The press dieaccording to claim 17, characterized in that: some of the press dies areconfigured to be moved and positioned by a back gauge of the processingapparatus in the intersecting direction; and the press dies to be movedand positioned by the back gauge in the intersecting direction are eachprovided with a stopper which the sheet material is brought into contactwith.
 19. The press die according to claim 15, characterized in that thepress die comprises a hemming part to hem the sheet material.
 20. Thepress die according to claim 19, characterized in that the hemming partis configured with the end face pressing part.
 21. A die setting bodyinstalled on and used by a processing apparatus that employs a punch anda die to bend a sheet material, characterized in that the die settingbody comprises: a die setting part on which the die is set; and an endface pressing part that presses an end face area of the sheet materialalong a bend line along which the sheet material is bent by the punchand the die set on the die setting part, the end face pressing partbeing positioned opposite to an apparatus base of the processingapparatus with a pressurizing center of the punch and die beinginterposed between the end face pressing part and the apparatus base.22. The die setting body according to claim 21, characterized in thatthe end face pressing part is divided into a plurality of press dies ina direction of the bend line of the sheet material to be bent, thedivided press dies being configured to be selectively used when pressingthe end face area extending along the bend line of the sheet material.23. The die setting body according to claim 22, characterized in thatthe selective use of the divided press dies is realized by configuringeach of the press dies to be moved in a direction intersecting with adirection in which the punch is driven toward the die set on the diesetting body to bend the sheet material between the punch and the die.24. The die setting body according to claim 23, characterized in that:some of the press dies are configured to be moved and positioned by aback gauge of the processing apparatus in the intersecting direction;and the press dies to be moved and positioned by the back gauge in theintersecting direction are each provided with a stopper which the sheetmaterial is brought into contact with.
 25. The die setting bodyaccording to claim 21, characterized in that the die setting bodycomprises a hemming part to hem the sheet material.
 26. The die settingbody according to claim 25, characterized in that the hemming part isconfigured with the end face pressing part.